var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');// 浏览器的logo 
var logger = require('morgan');// 日志输出
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');// 对返回值的转换
var ejs = require('ejs');
var index = require('./routes/index');
var users = require('./routes/users');
var goods = require('./routes/goods');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));// 说明views文件夹就是server文件夹里的views
// 定义怎么去寻找
app.engine('.html', ejs.__express);
// 视图引擎
app.set('view engine', 'html');

// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));// 使用该插件
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

// 登录拦截，通过cookie判断
app.use(function(req, res, next) {
	if (req.cookies.userId) {
		next(); // 已经登录过，直接进行下一步
	} else {
		// req.originalUrl为原始的url,当前地址
		if (req.originalUrl == '/users/login' 
			|| req.originalUrl == '/users/logout' 
			|| req.path == '/goods/list' ) {
			next();
		} else{
			res.json({
				status: '10001',
				msg: '当前未登录',
				result: ''
			});
		}
	}
});

app.use('/', index);
app.use('/users', users);
// 定义一级路由
app.use('/goods', goods);

// catch 404 and forward to error handler,全局404的拦截
app.use(function(req, res, next) {
  var err = new Error('Not Found');
  err.status = 404;
  next(err);// 后面执行，当404或者找不到的时候就用err阐述，否则继续执行
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;
